how to filter array same element in javascript code example

Example 1: how the filter() function works javascript

const arr = [1, 2, 3, 4, 5, 6, 7, 8, 9];

const filter = arr.filter((number) => number > 5);
console.log(filter); // [6, 7, 8, 9]

Example 2: javascript to remove duplicates from an array

uniqueArray = a.filter(function(item, pos) {
    return a.indexOf(item) == pos;
})